1. Field of the Invention
The present invention relates to a superconducting device provided with a superconducting thin film of an oxide, specifically of the Tl-Ba-Ca-Cu oxide, and a method of producing the superconducting thin film.
2. Description of the Prior Art
Recently, it has been discovered that the Tl-Ba-Ca-Cu oxide exhibits a superconductivity at a critical temperature (120 K) higher than the boiling point of liquid nitrogen (77 K), which attracted attentions of the researchers and engineers (41 NATURE VOL. 332 Mar. 10, 1988 pages 138-139). This superconductor prepared from the Tl-Ba-Ca-Cu oxide is advantageous in a high critical (transition) temperature, without any rare earth element.
In a device such as a superconducting transistor, a superconducting quantum interference device (SQUID) or the like, a thin film superconductor is used. Consequently, it is necessary to prepare a thin film of superconductor Tl-Ba-Ca-Cu oxide and produce a superconducting device.